Idiopathic pulmonary fibrosis (IPF) is a progressive fibrotic disease of the lung unaffected by currently[unreadable] available medical therapies. Although traditionally considered a chronic progressive disease it has been[unreadable] recently recognized that patient's course may differ and that while some patients have a chronic slow decline[unreadable] in their pulmonary functions others have a more accelerated course characterized by "acute exacerbations".[unreadable] The variable course of the disease and the recent observation that improvement in patient survival does not[unreadable] have to be associated with an improvement in traditional pulmonary function tests, suggest that traditional[unreadable] methods for tracking IPF progression may at best serve as chroniclers of a forgone conclusion and not[unreadable] provide any useful information about disease progression. We hypothesize that host defense factors,[unreadable] potentially but not necessarily associated with the primary cause of the disease, determine the rate of[unreadable] disease progression. Characterizing these factors will allow us to identify an integrated set of surrogate[unreadable] biomarkers in the peripheral blood that correlate and potentially predate IPF progression. The proposal has[unreadable] the following specific aims:[unreadable] 1. To create, using the Simmons Center ILD Database and referral base, and the Short term IPF[unreadable] outcome study, a cohort of carefully characterized IPF patients that will be prospectively clinically[unreadable] followed up according to current clinical practice guidelines.[unreadable] 2. To analyze protein expression levels in the serum of target molecules using a multianalyte bead[unreadable] based protein profiling assays assay.[unreadable] 3. To identify a gene expression signature in PBMC that is diagnostic and relevant to disease[unreadable] progression and treatment effect.[unreadable] 4. To determine the role of adaptive immunity in IPF disease progression.